Breather type storage apparatus for gases and volatile liquids



Aug? 7 1943. .2. H. WIGGINS 4 2,327,084

BREATHER TYPE STORAGE APPARATUS FOR GASES AND VOLATILE LIQUIDS Filed March 15, 1941 2 Sheets-Sheet l INVENTOR;

ATTORNEY Aug. 17, 1943,

J; H. \NIGGINS BREATHER TYPE STORAGE APPARATUS FOR GASES AND VOLATILE LIQUIDS Filed March 15 1941 FIGS.

2 Sheets-Sheet 2 INVENTOH;

JOHN H. W/GGINS A TTOFI'NEY Patented Aug. 17, 1943 OFFICE BREATHER TYPE STORAGE APPARATUS "FOR GASES AND VOLA'lIILl-E LIQUIDS John H. W ggins, Chicago, Ill. Application March 15, 1941, Serial No. 383,525

This invention relates to tanks and containers 1 10 Claims.

that are used for storing gases and/or volatile liquids, and particularly storage apparatus of the kind that are equipped with .a breather type roof or balloon roof, which'is adapted to flex or move vertically so as to vary the internal volume of the container. 7

One object of my invention is to provide a storage apparatus of the general type mentioned, whose roof is constructed in a novel manner that greatly decreases the amount of rain water that can possibly collect on the roof, if the drainage system of the roof becomes clogged, or even if the roof is not provided with a drainage system.

Another object is to provide a storage apparatus of the general type mentioned provided with a roof whose top area'is made up of steeply pitched or sharply sloped drain surfaces, that lead to a water collection trough located relatively close to the peripheral edge of' the roof. 7 Another object is to provide a breather type or balloon type roof for storage tanks and containers, which is of such design or construction that the flexible portion or portions of the roof, while passing from a downwardly inclined into an upwardly inclined position, or vice versa, will move through a horizontal plane, noiselessly and with a minimum of wrinkling of the roof plates.

Another object is to provide a breather or balloon type roof for storage tanks and containers,

structures used with breather and balloon type roofs of conventional design.

And still another object of my invention is to increase the capacity of storage apparatus of the kind and type above referred to, without adding to the cost of building or erecting the apparatus.

Briefly described; the tank roof that constitutes my present invention, is composed of a. flexible, substantially washer-shaped peripheral portion having its outer edge attached in a gastight manner to the side wall of the tank and projecting inwardly from said side wall towards the center of the tank, a stiff, vertically-disposed tubular member, hereinafter referred to as a cylindrical-shaped, polygonal-shaped rim, attached in a gas-tight manner to the inner edge of said washer-shaped peripheral portion and projecting upwardly from same, and a central roof portion having its outer edge attached in a gas-tight manner to thetop edge of said rim, said peripheral portion and central portion lying in different vertical planes, or, in other Words, being disposed in such relationship that the peripheral portion surrounds the central portion or lies beyond or outside of the vertical zone in which said central portion is located. Said central roof portion may comprise or consist of a cone-shaped or convex-shaped part, it may comprise or consist of a flexible metal diaphragm, or it may be composed of a pluralit of flexible metal members or parts joined together by one or more interposed collars or ring-shaped connecting devices that maintain said flexible parts in different planes. The rim previously referred to that joins the inner edge of the flexible peripheral portion of the roof to the central or center portion of the roof, is preferably constructed. in the form of a stiff, tubular shaped, vertically-disposed member that may be 7 or any other preferred shape in cross section. It cooperates with the flexible peripheral portion of the roof, when the roof is flexed downwardly to form a water collection trough that is preferably equipped withone or more drains. The flexible peripheral portion, in'general shape or form, resembles a washer or flat annulus that is disposed at approximately right angles to the side wallof the tank and to the rim with which it co-acts'to form a water collection trough, as above explained, the said rim constituting a ye"- tical side wall for said trough and the said flexible peripheral portion constituting an inclined bottom for said trough.

The central portion of the roof, the flexible peripheral portion, and the interposed rim that joins said two portions together, are preferably so proportioned and combined that when the roof is in its extreme downwardly flexed position, the outer edge of the central portion of the roof attached to said rim, will lie in a horizontal plane coincident with or higher than the horizontal plane in which the top edge of the tank side wall lies. Accordingly, no matter how much water may collect on the flexible peripheral portion of the roof, said collected water cannot rise high enough to flow over the top edge of said rim, onto the central portion of the roof. In the preferred form of my invention, the center portion'of the roof is formed by a coneshaped or convexed part, which, in any and all positions of the roof, will be self-draining, or

capable of shedding water quickly and efiiciently from the same. Bearing in mind that said peripheral portion constitutes only a relatively small part of the total area of the roof and is so constructed or arranged that water which collects on said peripheral portion, even when the roof is in its extreme downwardly flexed position, cannot back up onto the central portion of the roof, it will be seen that the weight of an excessive or abnormal rain load does not have to" be taken into consideration in designing the supporting structure that sustains the roof when the roof is in its downwardly deflected position.

In fact, I have demonstrated that theta'nlrrocf herein described can be properlysustainedby'a roof supporting structure formed by permanent frame members of such weight and area, that a saving of approximatelyof the steel used in the roof inthe roof supporting structure is possible.

The central portion andthe peripheral portion of thereof areconstructedirem metal plates joined together by gas and liquid-tight joints. One objectionable feature orcharacteristic of the conventional breather or balloon type roof is that wrinkles of perceptible sizeform in the roof plates, and the plates buckle, hexandmalre a considerable noise, while therooiis moving through a'horizontal plane in: passing from its extreme downwardly flexed position into'its extreme upwardly flexed position, and'vice versal I have overcome the above mentioned'objectionable characteristic of theconventional breather roof. by dividing the area eftherootinto acen-P tral zone of relatively great radius,v joined'by a relatively heavy, vertica1lydisp osed rim to a. pcripheral zone of considerably lessradius. than the central zone, and imposing aneccentric load on said central zone. As: the, pressuregin the. gas space of the apparatus'rises, the peripheral zone of the; roof assumes an upwardly: flexed condition, withoutwrinkling ormalr ing a noise; before the rim leaves-or rises ofiof the roof supporting structure; andas the pressure'continuesto'rise, the rim'v starts tomove upwardly, but, on account of the eccentric. loadzc-n the central zone; the rim assumes. a slightly 'inclinedor' tilted. position, with the result that the inner edgecof I'the flexible peripheral'portion of the'rooi isleased up through the horizcntalp'lane, intermediate the two extreme flexed positionsof'said peripln eral portion, substantially noiselessly. and with a minimum of. stresses,..hereinafter'rmore. fully explained. Similarly, the inner: edgeofitlie flex; ible peripheral portion'of'the roof is'eased'down through the horizontal plane. without wrinkling or producing a noise duringtthe downward movement of the roof.

Figure-1 of'the. drawings is a fragmentary top plan view of my improved. apparatustlwithithe roof broken awayso as to show the roof supporting structure.

Figure 2 is a fragmentary, vertical transverse sectional view of the apparatus;.,

Figure 3 is a vertical transverse: sectional view, illustrating another form of myinventlon, wherein the central portion of the roof-isccmposed of two flexible parts joined together by an' interposed, ring-shaped"connecting member.

Figure 4 isa vertical transverse sectional view of an apparatus'in which the central portion'of the roof is formed "by'a'single metal diaphragm A1 designates the side wall of the tank or container, B designates the central portion of the roof which is constructed in the form of a. coneshaped or. convexed member, C designates the flexible peripheral portion of the roof that surroundssaid central portion or lies in a vertical plane thatis beyond or outside of the vertical planeinwhicli the. centralportion Bis disposed. said peripheral portion having its outer edge attached'ina gas-tight'manner to the side walI'A', and projectinginwardlyfrom said sidewall; and D designates the .rim whose opposite ends are attached in a gas-tight manner to the outer edge of the central portion'B and to the inner edge of "the flexible peripheral portion C. The rim D, which is of stiff construction isherein illustrated as being formed-by alrel'atively heavy. cylindri cal-shaped member, disposed vertically and connected'by gas andJliquid-tight jointstothe two portions B andiC. Saidparts 3,0 and!) are so proportioned and combined. that when. the roofis in its extreme downwardly flexed condition, as shown in solid. lines in Figure 2, tho top edge of'thev rim Dislocated inahorizontal plane that is either. coincident with-or slightly above the horizontal planev in.which.the top. od9c of the tank side wail A lies. Inthe partieular form of'my invention herein shown, theradiui of the flexible peripheral 'portlonC is only $IIM tional' part of the radius of the: entire: :00. When the internal pressure of the gas space of the tank is not greatenouglrtomaisethe root or flex it upward1y-,.th'e flexible peripheral-pep tion. CJ'slopes-downwardly and inwardly; who sharp pitch, from the peripheral edgeof the roof, thusforming a water collection-trough or val ley'sc'at'the point where said peripheralportioa Joins or merges into.the rim=D.. Iii-this position of'the roofit is impossible for rainlwater in the trough a to back up onto the centralportionB ofthe roof, due, of course to thefactthat thc top edge of therimD ishigherthan ttielevel of any, load of 'Water thatlcan collect-inane! remaln insa'id Itrougd-even thoughlthe drain-outletl at'the lower end'of said troughbecomes clogged. When the roof moves upwardly intoits extreme elevated position, the peripheral portion-C assumes such a shape. or formthatany water thereonwhich fails toescape. through th e dmin 1, will be discharged radially at the-peripheral edgeof said portion C.- Atlall .times,..i. e-,.whon the'rocflis in its extreme downwardly-flexed position, or extreme elevated'position, or while-tho roof is passing from one extreme position tmtfie other, thecentr'al portion B of the roof remains in such a shape I or form that rain. water-will drain ofi of same, rapidl and efficiently. onto the peripheral portion'C.

When the roof is'in it'sdoivnwardly-fiexed position; it is'sustainedb'y a supporting structure that mayltetmade of considerably. less area and load.- carrying capacity than the'supporting structure of the conventional breather type roof, due to the fact that my improved roof is of such design that no relatively great load of rain water can collect and remain on the roof. Preferably, said roofsupporting structure is so made that after the reel plates have been welded together and combined with the rim D, said supporting structure can be modified or adjusted in a Way that stretches the roof plates and causes the-two portions B and C of the roof to assume'a shape or form that adds considerably to the storage capacity of the apparatus without increasing the size of the apparatus or the cost of building the roof. in the form or" my invention shown in Figures 1 and 2, the roof supporting structure comprises permanent frame members consisting of uprights circumferentially-disposed beams 3 sustained said uprights, radially-disposed rafters 4 extending inwardly from the side wall or the tank and supported at their inner ends by the beams carried by one circular row of uprights 2, and a second set of rafters 5 extending radially from a center upright and supported at their outer ends by the beams 3 carried by the second circular row of uprights 2. Said supporting structure also comprises temporary frame members consisting of removable blocks 6 positioned under the lower ends of the uprights 2, and a set of removable, radially-disposed rafters 1 supported by the two sets of circumferentially-disposed beams 3, said rafters I being shown in broken lines in Figure 1, so as to indicate that they are removable. In constructing the roof, the roof plates are first laid on the rafters l, 5 and I, and welded together while the blocks 6 are positioned under the uprights Thereafter, the blocks 6 and the rafters "I are removed, thus causing the two portions B and C of the roof to assume a sharper downward pitch or angle. This downward movement or deflection of the portions B and C causes the plates from which said portions are constructed to be stretched, with the result that the area of the roof is increased by the stretching of the roof plates, and any slight wrinkles in said plates are'removed. Increasing the area of the roof by such stretching of the roof plates, coupled with the sharp downward pitch of the flexible portion of the roof, increases the-storage capacity of the apparatus, without adding to the cost of the roof, and removing wrinkles from the roof plates, elim nates uneven surfaces on the top side of the roof that might tend to cause rain water to form puddles on the roof, or not flow freely over the roof. I have found that a supporting structure of the kind above described forms an adequate support for the roof when it is in its downwardly-deflected position, notwithstanding the fact that said supporting structure comprises fewer frame members, and frame members of considerably less weight than those used in the supportin structure of the conventional breather type roof, this being made possible, as previously stated, because the shape or form of the roof and the way in which the two portions B and C of same are combined with the rim D, precludes the possibility of an abnormally large or heavy load of rain water ever collecting and remaining on the roof.

During the upward and downwardmovement of the roof, the flexing of the roof plates is controlled in such a way that the roof is practically noiseless in operation, and wrinkles do not form in the roof plates to retard or interfere with the drainage of rain water. These highly desirable "flowing to the drain I leading from said gutter.

results are attained by incorporating the stifl, heavy rim D in the roof and arranging a weight or load E eccentrically on the central portion B of the roof, at one side'ofthe edge of said portion, as shown in Figure l. The combination of said heavy rim and eccentric load also insures rapid and eihcient discharge of rain water through the drain I that leads from the water collection trough or valley as. If the plates constituting the two portions B and C of the roof are of the same thickness, then the area B of the roof inside the rim D is, on the average, heavier than the flexible peripheral area or portion C. Aspressure in the gas space rises, then the first movement is in the portion C. Said portion C will flex upwardly all around (as shown on the left hand side of Figure 5), before the rim D leaves the roof supporting structure at any point. The rim D constitutes a very heavy weight-about 5 to 10% of the weight of the entire roof plates. Thus, as the peripheral portion C rises, it is flexed up as an entirety throughout its entire area, before its inner periphery or edge portion moves upwardly bodily. As a result of this action, the peripheral portion of the roof rises noiselessly and without forming wrinkles of the kind that always form in the peripheral portion of the conventional breather roof, during vertical movement of the roof in either direction. As the pressure continues to increase, the rim D begins to rise, but it assumes a tilted or angular position, due to the weight imposed on the outer edge of the central portion B of the roof by the eccentric load E. In other words, the weight or load E holds down one side of the rim D, while upward pressure is being exerted on the other side of the rim. In addition to controlling the flexing of the roof, as hereinafter explained, this tilting action of the rim' imparts a slight circumferential pitch to the trough or gutter ac, in a direction that insures any small puddles of rain water in said gutter A further increase in the internal pressure of the gas space, causes the rim D to move bodily in an upward direction, the rim remaining in its tilted or angular position, until the high side of the annular peripheral portion C of the roof gets tight enough to hold back said high side. Thereafter, the low side of the peripheral portion of the roof rises faster than the high side, and the rim gradually assumes a level or horizontal position as the roof reaches its extreme upwardly flexed position. However, the high side of therim passes through the horizontal plane in which the top edge of the tank side wall A lies, before the low side of the rim reaches said horizontal plane. The inner edge of the flexible annular portion C of the roof is thus eased up through the intermediate horizontal plane lying between the two extreme positions of the flexible portion C of the roof, noiselessly and with a minimum of stress. During the downward movement of the roof, the inner edge of the flexible portion C is eased down through the intermediate horizontal plane in a similar manner, the stiff rim D causing the peripheral portion of the roof to rise and fall in a plane, during the upward and downward movement of the roof.

In the form of my invention illustrated in Figure 3, the central portion of the roof carried by the rim D is formed by a flexible diaphragm 8, whose outer edge is attached by a collar or ringshaped connecting device 8 to an annular flexible member 8 that is fastened to the top edge of the rim D, the diaphragm 8 being provided adjacent its outer edge with an eccentrically-disposed- W ht orloadE', andthe annular'flexible part 33 being'provided with. an eccentrically-dis-- In a roof oi thisparticular con posed-load EL struction, the flexiblecenter diaphragm- 8' will flex upwardly first, because. thatis the portion'of' the roof having the 'lowe'st average Weight- Next, the-collar ring-shaped connectingv device 8* will move upwardiv, and'in'ally, the rimDwillrise. This method of constructing the. central portion of thereof gives aconsiderable increase inavailable-vclume change; at a very little expense of increase in water load. The flexible annular part E' 'and the: collar Saw-illoperate" just as if the out r edge of said part 8 "were-at-- breather roof as the accumulated slope. in the-- peripheral portion C, plus portion-8 plus diaphragm the accumulation cf: wrinkles'necese saryto the entire roof up through-a hor zontal plane would be so great that the plates or welded jointsof thereof would crack. But each of the parts'C, 8 and it of the rocf'ope-rate entirely independently of each other; as far astheir own flexing is concerned.-

In the form of invention shown in Figure 4, the central portionof the roof is formedby a conventional breather roof diaphragm 9, provided adjacent its outer edge- Wlth eaten-- trically-dispose'd weight or load E. Fro-m the previous description of my. invention the ope-ration of the roof shown in Figure 4.- willbe obvious.

Figure 6 illustrates feature thatmay be in ccrporated in a roofof kind-shown in Figures 1 and 2; Said feature consists of a means for conducting rain water off the central portion of the roof, without the necessity of said Water first draining onto the flexible peripheral portion of the roof, and means for preventingu'ain from backing up on the peripheral portion and. flowing onto the central portion B'of the roof, in the event the outer edge ofthe centralportion of the roof ever reaches a position lower than the top end of the side wall. As shown in said Figure 6, the rim D is extended upwardly above the outer edge or the central portion B, so as to form a baffle or water trap It] that prevents a load of rain water in the gutter or valley x -from ever backing up ontothe portion B. A drain ll leads outwardly from the inner side of the bafl'ie iii, so as to discharge rain water directly;

from the portion B, over the top edge-oi the side wall of the tank.

Having thus described my invention, what I claim as new and do r to secure by Letters Patent is:

1. A breather type roof for storage tanks,

edge of said peripheral portion, that tends to pro-- vent said in er edgefromrising or moving upwardly bodily, until after said peripheral portion hasbeen plaoedunder considerable tension-by.

the pressure-of the gases confined in the tank 2; Atarik roofof the lcind describedtn dab; 1; which also includes a means-for cansingthe central portion'of' the roofv and-said rim to tilt: during; the' bodily upward movement of the inner edge-part of thcperipheral portion of the roof;

3'; A storage apparatus, comprising: a container or: tank; and a-brcather typeroof connected to the tank side-wall by a gas and liquid-tight joint; and composed of aperipheral portion that is capable-of flexing-upwardly and downwardly through" ahorizontal plane, a center portion lying, in; a different vertical plane than said peripheral portion and-constituting a large non tion of the areaof the roof, said center portion being of less-diameter than the side wall of the tank;- and: a substantially annular-shaped, eccentrically-loaded rim, attached to the inner' edge ofsaid peripheral portion andto-the outer edge of said center portienand disposed so as to always maintain the ou-teredge of said center portion in-ahighei horizontal plane than theimlcr edge ofsaidpe-riphera1 portion so that waterthat may collecton said peripheral portion is pro-- vented'frorn flowing onto said central. portion, saideccentrieally-loaded rim being so constructed'and arranged that said central portion and said rimwilltilt during the upward movement of the inner edge part of said peripheral portion.-

fl. An apparatus of the-kind described in clam 3 in which the top edge of saidrim when the roof is in its downwardly-flexed position, ls-lncatedin a-horizontal plane coincident with 'or higher than the horizontal plane in which the top edge of the tank side-wall lies.

5 Ah apparatus-of the kinddcscribed in claim. 3, in which the'center portion of the roof iscoueshaped. or convex-shaped; in any and all post-- tions of the roof.

6'. An-apparatus of the kind described in claim inwhicli the center-portion of the roof isformed by a metal diaphragm that is capable of flexing upwardly and downwardly.

7. An apparatus of the kind described in claim 3, in which the center portion of the roof is f'ormedby a plurality of concentrically-arranged, flexible parts and an interposed ring-shaped cann'e'cting device that maintains-adjacent edges-of said"concentrically-arranged parts in diiferent horizontal planes.

8. A storage apparatus, comprising a tank, a'b'reather type roof; comprising a. flexible, washrer shap'ed'g peripheral portion having: its outer edge attachedin a gas-tight manner to the side Wallof the tank and projecting inwardly from said side wall; a center portion of relatively great radiusbut of' considerably less diameter than the side 'wa-ll'of' the tank, disposed in a, different vertical plane than said peripheral portion, an interposed, vertically-disposed, cylindricalshape'd" rim of stiff construction attached in a gas-tight manner to the inner edge of said erip'h'eral portion andtotheouter edge of said center" portion and extending continuously. around the roof, so'as to maintain the center portionin'a higher horizontal plane than the peripheral portion and prevent wateffrorm nowing from said peripheral portion onto said CE!!- ter portion, and means for causing said rimand centerrportio'n ttitiltduring the upward-movement'of the' inner edge of said peripheral 'pm'ti oii during -the'vertical movement of the root 1 9. A-stora'ge apparatus, comprising' a tzmfiu breather typeroof comprising afioxible; wash;

er-shaped, peripheral portion having its outer edge attachedin a gas-tight manner to the side wall of the tank and projecting inwardly from said side Wall, a center portion of relatively great radius but of considerably less diameter than the side wall of the tank, disposed in a diiferent vertical plane than said peripheral portion, and an interposed, vertically-disposed, cylindrical-shaped rim of still. construction attached in a gas-tight manner to the inner edge of said peripheral portion and to the outer edge of said center portion and extending continuously around the roof, so as to maintain the center portion in a higher horizontal plane than the peripheral portion and prevent water from flowing from said peripheral portion onto said center portion, said rim being relatively heavy and the center portion of the roof being provided with an eccentrically-disposed load so as to cause said center portion and rim to tilt during the upward movement of the inner edge part of said peripheral portion.

10. A storage apparatus, comprising a tank, a breather type roof, comprising a flexible, washer-shaped, peripheral portion having its outer edge attached in a gas-tight manner to the side wall of the tank and projecting inwardly from said side wall, a center portion of relativelygreat radius but of considerably less diameter than the side wall of the tank, disposed in a different vertical plane than said peripheral portion, an interposed, vertically-disposed, cylindrical-shaped rim of stifi construction attached in a gas-tight manner to the inner edge of said peripheral portion and to the outer edge of said center portion and extending continuously around the roof, so as to maintain the center portion in a higher horizontal plane than the peripheral portion and prevent water from flowing from said peripheral portion onto said center portion, and means for causing said rim and center portion to tilt during the upward movement of the inner edge of said peripheral portion during the vertical movement of the roof, said center portion comprising the following elements, to wit: (1) a central disk; (2) a substantially horizontally-disposed, washer-shaped part arranged in concentric relation with said disk in a different horizontal plane; and (3) a vertically-disposed, tubular member attached to the outer edge of said central disk and to the inner edge of said washershaped part.

JOHN H. WIGGINS. 

